1. Field of the Invention
The present invention relates to a vertebral locking and retrieving system.
2. Description of the Prior Art
In general, conventional vertebral locking and retrieving systems of the prior art involve a locking process of multiple vertebrae, as exemplified by the LUGUE rod and the HARRINGTON rod, both made by Zimmer Company of U.S.A., and the ROY-CAMILLE plate produced by Howmedia Corporation of U.S.A. Such known prior art arrangements require a surgeon to make a long incision, which generally takes up too much of a surgeon's time and may bring about excessive bleeding by a patient receiving the treatment. The case in point is the LUGUE rod, which must be secured to two upper and lower vertebrae immediately adjacent to the injured or the deformed vertebra. This means that a surgeon is required to make a large incision to fix at least five segments of the spinal column. As a result, the patient's ability to move about is greatly hampered in the wake of such a surgical operation. In addition, the pressure exerting on the patient's nervous system by the locking and retrieving system of the prior art can not be effectively mitigated in view of the facts that the locking process is confined to a rear plate and that the retrieval of a front plate is not possible.
Furthermore, the surgical implantation of the conventional vertebral locking and retrieving systems of the prior art is further complicated by the fact that seven cervical vertebrae, twelve thoracic vertebrae, five lumbar vertebrae, and one caudal vertebra of the human spinal column differ in curvatures.
Other types of prior art vertebral locking and retrieving systems are disclosed respectively in U.S. Pat. Nos. 4,611,581 and 4,696,290. Such systems have also failed to deal with the surgical problems described above. In short, the existing vertebral locking and retrieving systems of the prior art have failed to address the surgical problems that are derived mainly from the fact that the curvatures of various vertebrae of the human spinal column are different from one another.
It is therefore the primary object of the present invention to provide a vertebral locking and retrieving system with locking pin assemblies which are designed in such unique manners that they have specific angles permitting the locking pin assemblies to cooperate with the specific curvatures of various vertebrae and that they serve to overcome the problems during and after the surgical operation having to do with locking multiple vertebrae.
It is another object of the present invention to provide a vertebral locking and retrieving system with means which can be used to lock two vertebrae of the spinal column.
It is still another object of the present invention to provide a vertebral locking and retrieving system with locking pin assemblies designed to have specific angles for correcting the position of various vertebrae having different curvatures.